Final answer:
The correct answer is (b) Extensive agriculture, which uses large areas of land with minimal labor per hectare, resulting in low yields and low population densities.
Step-by-step explanation:
The type of subsistence agriculture that involves large areas of land with minimal labor input per hectare, resulting in both low yields per land unit and low population densities, is referred to as extensive agriculture. This mode of subsistence contrasts with intensive agriculture, which is characterized by farming a single plot repeatedly with labor-intensive methods like plowing, terracing, and irrigation to mass-produce commodities. Extensive agriculture requires large parcels of land which allows for greater space between crops; this type of farming is commonly used to grow crops that do not require as much attention and can be left to grow over large areas, such as wheat and other grains.
Farmers practicing extensive agriculture typically have access to less valuable land and cannot afford, or do not need, costly farm labor. The surplus from such farming is less when compared to intensive agriculture, which supports large populations and creates a variety of socioeconomic roles including craft production, trade, and more, representing a shift towards modernity in agricultural societies.